Battle of Portchester

The Battle of Portchester was fought in 881 during the Viking invasions of England. An invading Viking fleet from Nordmann landed to the south of Portchester in Hampshire, southern England, where it was brought to battle by King Alfred the Great himself and defeated. The Viking king Aemund and the vast majority of his army were killed, and its remnants fled to the Isle of Wight, where it was pursued and destroyed shortly after.

Background
In the spring of 881, King Alfred the Great of Wessex received reports that a small raiding force from Nordmann was seen approaching Britannia from the south, arriving in just a few months. Upon hearing of this, Alfred had to march south from the East Anglian border with his army. Further reports showed that the Nordmann fleet was approaching the unprotected Isle of Wight, and it ultimately made landfall at Gosport to the south of Portchester. Before the Vikings could lay siege to the important port city, King Alfred and his army arrived, and the Nordmann army decided to attack, hoping for a victory despite having a poor chance of success.

Battle
King Alfred arrayed his army in layers, with his melee infantry forming the first row, his missile infantry forming the second row, and his own person and retinue in the third row; cavalry units were positioned on either flank. The Nordmann army charged into battle, with its cavalry units failing to outflank the West Saxons; the West Saxon line was stretched wide, and the right and left wings were able to charge against the Nordmann forces, who were concentrated in the center of the battlefield. In addition, the West Saxon cavalry, who had chased off the Nordmann cavalry, successfully outflanked the Nordmann forces and charged their rear, further trapping the Vikings. Aemund and several of his other retreating warriors fell in a great slaughter, and Magnus of Nordmann led the remnants to the Isle of Wight, where the West Saxons caught up to them and destroyed them in another, albeit less competitive, battle. The Nordmann threat was ended in a single battle, with a few of their warriors being pressed into West Saxon service.